The wingspread range is 4 7/16-5 1/8 inches (112-132 mm) (Opler and Malikul 1992). The upper surface of the wings is black with yellow markings. The front wing has a double row of yellow spots on the distal one third. The hind wing has a marginal row of yellow spots and a submarginal yellow band. The tails may have a yellow stripe down the middle.

Eggs are pale yellow-green. Older larvae are green with a pale yellow lateral line edged beneath with a fine black line. The underside of the larva is pinkish-brown. Abdominal segments have a transverse band of six blue dots with each dot ringed by a fine black line (much thinner than those on larvae of the spicebush swallowtail, Papilio troilus). One dot on each side is beneath the lateral line. There are a pair of large tan false eyespots lined with black on the rear of the thorax. The eyespots have a large black center and a white "false reflection" above. Larvae also have a smaller pair of tan spots at the front of the abdomen. Pupae are green with a white lateral line edged above with a purple-brown line. Pupae have two short horns.

There are several flights in Virginia (May-September) and many flights in Florida from March to December. The host plants are primarily species of Persea (Lauraceae) (particularly redbay, Persea borbonia (L.) and swampbay, Persea palustris (Raf.) Sarg.). Several other Lauraceae are listed as occasional hosts including Sassafras albidum (Nutt.) Nees. Sweetbay, Magnolia virginiana L., is also listed as a host, but in laboratory studies, larvae refused to eat it.

Eggs are laid singly on host plants and larvae eat foliage. Larvae spin a silk mat on a leaf which contracts to curl the leaf upward. They rest on the silk mat. Pupae hibernate. Males patrol wooded areas in search of females. Adults feed on nectar from a variety of flowers with a particular fondness for thistles. Adults also sip water and minerals at mud.